Clinch nut anvil with nut-positioning sleeve



June 28, 1949. w. STEVER 2,474,501

7 CLINCH NUT ANVIL WITH NUT-POSITIONING SLEEVE Filed Aug. 28, 1946 v 1 5 I. v I

I "I M @II w A llllllilllll 'mmmun I N VEN TOR WiULam Siauet BY z E ATTORNEY Patented June 28, 1949 1 Y CLINCH NUT ANVIL WITH NUT-PO81 TONING SLEEVE Y William Stever, Philadelphia, Pa., reign. to The Budd Company, Philadelphia, Pa., a corporation of Pennsylvania Application August 28, 1946, Se1:ialNo. 693,481

The invention relates to an anvil of clinching or riveting machines and especially to an anvil provided with means for holding a-nut, rivet or the like in a predetermined position. Still more specifically, the invention relates to an anvil of machines used" for 'securingso-called clinch nuts to panels, such as to panels of automobile bodies.

Among the objects of the invention is an anvil which has a longer life than anvils ordinarily used for the same type of work.

Another object of the invention isto provide an anvil for machines of the indicated type and for the indicated purpose which lends itself to the easy and convenient location on the anvil of the nut, rivet or the like preparatory to the riveting or clinching operation.

The objects of the invention are achieved outstandingly by an anvil provided with means for holding the nut or the like in the desired position, which means are supported by the anvil resiliently in the direction of the riveting blows so that the hammer of the riveting machine, when operated without a nut or the like in place, will not damage or destroy such means and thereby the anvil, as is frequently the case with presently used anvils having rigid positioning means.

More specifically, the invention contemplates the substitution of the rigid pin and ledge provided on customary anvils for holding a clinch nut in the desired position by a separate sleeve held by and surrounding the anvil and projecting beyond its Working surface, which sleeve is shaped to conform to the contour of the nut or other article to be riveted. Even'if such sleeve should get damaged it can easily and cheaply be replaced by a spare sleeve without much loss of time.

The above outlined and further objects, advantages and features of the invention will be more fully disclosed by the embodiments illustrated in the attached drawing and described hereinafter:

In the drawing;

Figure 1 is a diagrammatic perspective view of a fragment of a panel having secured in a hole thereof a clinch nut;

Figure 2 is a section on line 22 of Figure 1;

Figure 3 is a fragmentary side elevation, partly in section along line 33 of Figure 4, of the upper end of an anvil showing in dot-and-dash line a clinch nut held in working position;

Figure 4 is another elevation viewed in the direction of the arrows 4-4 of Figure 3;

Figure 5 is a plan view of the anvil viewed in the direction of the arrows 5-5 of Figure 3;

3 Claims. (01. 218-1) Figure 6 is a fragmentary elevational view of a modified form of the new anvil; and

Figure 7 isa section along line 'l-'l of Figure 6.

Clinch nutsfll) as illustrated in Figures 1 to 4 have one sideflattened off at I l in a plane spaced from the threaded hole It and parallel to the axis of the "latte-12f Except on the flattened off side, the nut'is recessed'at [3 to provide a radially outwardly extending shoulder l4, and the cylindrical axially extending portion 15 is of less diame-' ter than the projection of shoulder It. The end surface of the portion i5 is preferably tapered inwardly, as at I6, so as to provide in the unset nut an edge I! which can be easily hammered outwardly and downwardly. The sheet or panel I8 has a hole of a shape and size corresponding to the projecting portion l5, that is, a hole having a part-circular portion and .a straight portion. After the nut is placed with its portion l5 in the hole of the panel I8 in the only possible position, that is, with the flattened surf-ace ll of the nut coinciding with the straight side of the hole, the.

edge I! is riveted down to the position shown in Figures 1 and 2 and thereby the nut is integrally and permanently united with the panel.

customarily, one nut at a time is placed on an anvil of a riveting machine in a position predetermined by guiding means provided on the anvil, then the panel provided with a corresponding hole is placed on the nut, and finally the hammer of the power driven riveting machine is actuated to rivet or clinch down the projecting edge I].

The new anvil for the indicated type of riveting machinewhich, however, with appropriate modifications, may serve for solving similar prob- ,lems for riveting or clinching other objects-has a stem H! of circular cross section in its lower portion but flattened at 20 near its upper end on one side so that its end surface 2| corresponds to the shape of the collar M of the clinch nut. A countersunk hole 22 in the surface 23 prevents any burr on the thread of the nut from being squeezed. in the nut hole l2 which would cause deformation of the thread and might render the nut unusable.

The flattened portion 20 terminates at a transverse groove 23 which in turn is followed by an introduction of a nut from the left side in Figure 3. It will be apparent that the projecting portion of the sleeve 25 will hold a nut in a predetermined position.

The sleeve has a resilient downwardly projecting tongue 26 ending in an inclined bead 21 which normally engages the notch 23 and the inclined surface 24. The purpose of this arrangement is to hold the sleeve 2! normally in the position illustrated in the drawing. If, however, a

heavy pressure is exerted on the sleeve, such as by operation of the riveting hammer (not shown) without a nut on the anvil, then the sleeve 25 can recede against the action of the spring tongue 25, the lower end 21 of which is pushed outwardly by the inclined surface 24. As soon as the'pressure on the end of the sleeve 25 is relieved, tongue 26 will follow its tendency to straighten out and,-

consequently, slide inwardly on the surface 24 and'thereby move the'sleeve back to its original position.

It is obvious that operation of the riveting machine without a nut in place cannot do any serious harm to the anvil or the hammer because both are provided with large abutting surfaces and the only projecting portions, that is, the sleeve '25 for holding the nut in place, is resiliently'supported, so that it will give way under the action of the hammer.

In the emodiment illustrated in Figures 6 and 7, the anvil shaft 28 has an upper end 29 of reduced cross section, which latter is shaped to the form of the clinch nut. This end 29 is again surrounded by a sleeve 30 of corresponding shape and projecting beyond the working surface SI of the anvil. This sleeve is longitudinally slotted at 32, the walls of the slot having gently downwardly and outwardly inclined marginal portions 33 and more abruptly downwardly and outwardly inclined portions 34 so as to form a. slot with a widened central portion 35 and narrow end portions. Embraced by the margins of the slot is a radially and horizontally extending projection 36 which may be formed by the outer end of'a pin 31 secured by a screw or pin 33 in a corresponding hole of the anvil. The pin or screw 38 may be accessible from the recessed center of the working surface of the anvil.

The operation of the anvil according to the second embodiment is substantially the same as for the first embodiment. The only difference is that the spring action is derived from the transverse resiliency of the slotted sleeve and from the engagement between the inclined margins of the sleeve and the projection 36. Due to the surfaces 34, the sleeve cannot accidentally come ofithe anvil but it can be pulled off by using appropriate force. If the rivet hammer comes down on the anvil and the upper end of the sleeve without a nut being held in place, then the inclined margins 33 of the sleeve will engage the projection 36 and will permit the sleeve to move downwardly but will return it at once to its normal working position after the pressure on the end of the sleeve is relieved.

The invention is not restricted to the illustrated embodiment, but protection is sought for the invention as covered by the spirit and language of the attached claims. In particular, it is pointed out that different types of nuts or other articles will require modifications. Moreover, it is obvious that the resilient support of the sleeve may be achieved by various means although deriving resiliency without additional elements by the mere shape of sleeve and anvil is considered highly advantageous and constituting an inventive feature of practical importance.

What is claimed is:

1. Anvil for riveting machines comprising a sleeve surrounding the working end of the anvil and projecting partly therebeyond, a tongue provided on and extending in the axial direction of the anvil, an inclined surface provided on the anvil and engaged by said tongue so that pressure on the outer end of this sleeve will push the tongue against the inclined surface, thereby permitting the sleeve to be resiliently pushed back but returning the sleeve to its normal working position when the pressure is relieved.

2. Anvil for riveting machines comprising an axially slotted sleeve surrounding the working end of the anvil and provided with inclined margins on the slot, a projection on the anvil engaged by the margins of the slot so as to hold the sleeve normally in a position where it projects beyond the working surface of the anvil but to permit the pushing back of the sleeve by pressure exerted on its projecting end whereby the inclined surface and said projection spread the sleeve apart and return it to its normal position when the pressure on the end of the sleeve is relieved.

3. In a riveting machine for heading over an article having a base portion adapted to rest upon an anvil, and an upper portion designed to be headed over toward said base portion, the combination comprising an anvil and a workpositioning sleeve slidably embracin the anvil and projecting beyond the work-supporting face thereof, said sleeve including a portion which resiliently engages an adjacent complemental portion of the anvil to urge said sleeve normally into a position in which its free end may serve to locate the work on the anvil, whereby said sleeve may recede against said resilient holding action in response to a hammer blow against said sleeve, but will thereafter be restored by said resilient engagement to its aforesaid work-positioning location.

WILLIAM STEVER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PA'I'E'NTS Number Name Date 908,453 Caton Jan. 5, 1909 1,815,862 McCue July 21, 1931 2,301,888 Lear Nov. 10, 1942 

